1. Field of the Invention
This invention relates generally to carpet cleaning machines having suction means and carpet brushing means.
More specifically, this invention relates to a carpet cleaning machine having a reciprocating, carpet engaging brush driven by a mechanism which directly converts rotary motion to an arcuate, reciprocating movement.
2. Description of the Prior Art
A number of carpet cleaning devices utilizing a combination of suction means with a reciprocating, carpet engaging brush are known in the prior art. The brush itself is typically pivoted on arms and is reciprocated by action of an eccentric working through a connecting rod or cam means.
One such device is illustrated in U.S. Pat. No. 2,114,116 in which a shaft is eccentrically mounted in a belt-driven pulley and transmits reciprocating pivotal movement to an agitator or brush through a pin member operating in an arcuate cam way.
A more recent cleaning device combining a reciprocating brush with liquid cleaning means and suction pickup is shown by U.S. Pat. No. 4,014,067. In this device, a conventional eccentric operating through a connecting rod imparts a reciprocating action to a pivotally mounted brush.
It is also known to translate rotary motion into linear reciprocating motion utilizing a shaft having a crank portion set at an oblique angle to the shaft. One such device adapted for use in a reciprocating saw is illustrated in U.S. Pat. No. 2,824,455.
The translation of rotary motion to a reciprocating, arcuate movement by means of an eccentric introduces a considerable amount of vibration and noise into the operation of a machine. In addition, because of the stresses involved, an eccentric arrangement is inherently a high wear component.